LITTLE ROCK (AP) - Voters in the state's most populous county got an extra 90 minutes to cast ballots Tuesday under a court order won by Democrats who said several polling stations were running out of ballots.

Republicans accused the Democrats of trying to steal the election and appealed to the Arkansas Supreme Court, which ordered the polls closed in heavily Democratic Pulaski County.

It was unknown how many votes were cast before the court ruling.

Democrats sought the extended time shortly before the polls closed, saying many precincts had run out of ballots and some voters were discouraged from voting because of hour-long waits.

Lawyers for the Republican Party argued in a conference call with the high court that the election laws couldn't be changed at the last minute and applied differently to different voters.

The effect on votes cast after the normal 7:30 p.m. closing time wasn't immediately known.

Arkansas Supreme Court Chief Justice W.H. "Dub" Arnold said the court voided the order of Circuit Judge Collins Kilgore. But when asked how the ruling affects votes cast after the normal closing hour, Arnold said, "What effect it has, I don't know."

Charles King, the Pulaski County Election Commission chairman, said all the votes would be counted because there was no way to distinguish what time ballots were cast. He estimated the county had about 500 challenged ballots from problems with voting throughout the day.

The extension would seem to have benefited Democratic Party candidates, who have carried the county in U.S. Senate and presidential elections since 1992.

The county has nearly 16 percent of the state's 1.55 million registered voters, and the county's election results were considered critical to the closely watched U.S. Senate race between Republican incumbent Tim Hutchinson and Democrat attorney general Mark Pryor, as well as the governor's race and other statewide contests.

King said that regardless of how late the polls closed, the votes would be counted Tuesday night.

"We will not leave until all the ballots are counted," King said. "I know the eyes of the world are on us here in Arkansas tonight. The whole country is waiting on us."

The Hutchinson-Pryor race was among a handful of Senate races around the country that could determine which political party controls the national agenda and the U.S. Senate.

After Democrats won the extension, state Republican Party chairman Marty Ryall said GOP poll watchers were instructed to challenge every ballot cast after 7:30 p.m.

"This is an attempt by the Democrat Party to try to steal this as time runs out," Ryall said.

Democrats quickly put the word out to voters that they could vote until 9 p.m., recording a message by Rep. Vic Snyder, D-Ark., telling the electorate that the polls would remain open longer and urging them to vote for Democratic Party candidates.

Republicans said the hastily sent recording was proof that Democrats planned in advance to lengthen the polling hours.

But Michael Cook, executive director of the state Democratic Party, denied the allegation. Cook said that after people got off work and went to the polls to vote, many complaints came in of polls countywide running out of ballots. He said there also were complaints of long lines.

"Nobody should be disenfrancised regardless of their political preferences," Cook said.

He said the Democrats didn't ask the Republicans to join in their request because of the late hour.

King said he supported keeping the polls open, but he noted that officials got the word 10 minutes before the polls were to close and tell workers at 124 precincts. Ballot shortages were compounded by high voter turnout and a number of poll workers who waited until they were completely out of ballots before they called for more, King said.

Cook said the problem was more with the county clerk's office's failure to provide ballots in a timely matter when workers called in about running low.

Earlier, because of long lines and voter confusion, Pulaski County Prosecutor Larry Jegley said he would ask that a grand jury be convened to investigate the problems.

Jegley said the grand jury, which he hoped to have convened before the end of the year, would look into how the voter registration and the election system in the county could be improved, after months of snags in the Pulaski County clerk's office.

Also, Democratic officials initially said they were considering a court order to keep polls in Crittenden County open past the 7:30 p.m. voting deadline, but County Clerk Ruth Trent said officials there were able to keep used extra ballots and, in some cases absentee ballots, to avoid shortages.

In Clark County, the center of a student-voting lawsuit, said voter turnout among college students there picked up by the afternoon. County officials said student turnout was light in the morning, and had picked up by mid-afternoon at the Ouachita Baptist University polling site.

The county was the center of a two-week battle over student voter registration that resulted in a federal judge ordering students to be allowed to vote.

Phillips County officials said turnout at the polls was "fairly heavy."

"There are a few challenges in some polling places, but everything seems to be fairly routine otherwise," said election commissioner Joann Smith.

In October, the sanitation director for Helena pleaded guilty to voter fraud charges. And the state Republican Party has said it will ask the U.S. Attorney's office to investigate further allegations of voter fraud in Phillips County.

Baxter County's vote-counting system broke down, so county officials went north across the state line to Missouri to meet with a representative of the system's company. They planned to pick up a backup system and bring it back to the county to count the votes late Tuesday.